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Dopaco, Inc. - 2 - 10 February 2014 800 W. Church St., Stockton San Joaquin County 3. During a site walk and meeting on 5 February 2014, representatives from GC (Carolyn Kneiblher and Tony Smith) expressed concerns to Central Valley Water Board staff with the groundwater flow direction (to the north towards Church Street) due to conflicting data collected at nearby sites, specifically the McCormick and Baxter cleanup site. GC referred to reports from the nearby McCormick-Baxter Superfund site that shows a flow direction towards the south. We agreed that re-surveying the existing monitoring wells along with the new wells would be reasonable to verify the groundwater flow direction. 4. During the meeting, GC also requested input from Central Valley Water Board staff concerning tasks necessary to get this case to closure. Staff stated that to achieve closure of this case the following tasks must be completed o The horizontal and vertical extent of impacts from the toluene release (and any other chemicals comingled with the toluene) must be determined. o A declining concentration trend of all chemicals of concern must be established in groundwater. o A determination that no sensitive receptors (water supply wells or surface water bodies) are threatened by the residual pollution must be made. o The time for groundwater to reach water quality objectives should be predicted based on available data. o Once groundwater monitoring demonstrates that the pollutant plume is stable, and a site conceptual model is deemed adequate for understanding the distribution of the soil and groundwater pollution, a 60-day public comment period must be completed. Owners and occupants of properties within 500 feet of the pollutant plume will need to be notified of the proposed closure. o Finally, all monitoring and remediation wells will need to be properly destroyed prior to issuance of the No Further Action Required letter. 5. GC stated that the excavation will be delayed by two weeks due to a new City of Stockton excavation permit requirement for a geotechnical report, and that they would continue to give updates to us monthly by email. In the Work Plan, GC states DMW-513 will be installed within 45 days of Central Valley Water Board staff approval and a report of the well installation will be submitted within 90 days of that approval. Central Valley Water Board staff concur with the proposed installation of DMW-5B with the condition a shallow well targeting the sand zone directly below the excavation is installed and a Work Plan for installation of off-site wells cluster(s) is submitted by 30 March 2014. Please submit the following: • The excavation report and monitoring well installation report by 30 April 2014. • The deep well results and offsite well cluster(s) Work Plan by 30 March 2013. • The monthly status updates by email. If you have any questions or concerns you may contact me by phone at(916) 464-4615 or by email at jbarton waterboards.ca.ctov. /s/original signed by James L. L. Barton, P. G. Engineering Geologist UST Program cc list on next page